SD had a problem in the past about lieing if she had homework or not and she was failing because of it. DH, her teacher and I banded together and fixed that, she got A's and B's last semester.
But now she is lieing about other stuff.
Some I know is typical kid stuff.
"Did you clean your room?"
"Yes"
Go and check.
She's thrown everything in her closet... I get that...
But she lied ALL DAY saturday and sunday.
One was her room. Four times she just left her room and started watching tv. DH or I noticed her on the couch or heard her in the basement and,
"Is your room clean?"
"Yes"
"Completely? All clean clothes hung up? All dirty clothes in the laundry room?"
"Yes"
All clothes are shoved into a bin and shoved in her closet.
Infuriating that it happened so many times.
DH even confronted her, "Why all the lieing?"
"I'll clean it."
"No answer me. Why do you keep lieing. Not just about your room. Everything?"
"I don't know."

Some other things she lied about.
"I need new jeans. They all have holes in them." -Nope all were in tact and her size-
"I lost my flashdrive for school. I need another one." -Bought her a new one and watched her hang it on her lanyard RIGHT NEXT TO THE ONE SHE SAID SHE LOST! When asked about it, she said, "that's one from Brittany at school it's full so she gave it to me." -Bullshit! I bought it for her in August. It's bright orange, not hard to forget!
To DH, "I DIDN'T ROLL MY EYES!" Angry and crying. DH yells back at her, "I saw you!"
"I didn't roll my eyes."
"You can't lie about it when I saw you roll your eyes MYSELF!"
"I ONLY had one piece of pizza." -SS says to her, "that's crap. I saw you eat two and I wasn't even standing here the whole time."
"I was petting the cat and he bit me." -The cat was laying on my bed. In the other room no here near her.
"Can I take my lunch? They are serving hot ham and cheese tomorrow and I hate that." -OSD says, "You love the school's ham and cheese. I have lunch period with you and you always eat it. And they are serving pizza tomorrow not hot ham and cheese. And you love the school's pizza."

It's all petty little shit. But it's growing so frustrating!
DH is doing a good job of calling her out when he catches her.
However r I'm running out of calm voices to use...
I just keep saying- "That's a lie SD....This lieing has to stop....Do you want to be trusted?..."
I'm at the point I don't even want to talk to her.